A mobile network operator or MNO, also known as a wireless service provider, wireless carrier, cellular company, or mobile network carrier, is a provider of services wireless communications that owns or controls all the elements necessary to sell and deliver services to an end user including radio spectrum allocation, wireless network infrastructure, back haul infrastructure, billing, customer care, provisioning computer systems and marketing and repair organizations.

In addition to obtaining revenue by offering retail services under its own brand, an MNO may also sell access to network services at wholesale rates to mobile virtual network operators.

A key defining characteristic of a mobile network operator is that an MNO must own or control access to a radio spectrum license from a regulatory or government entity. A second key defining characteristic of an MNO is that an MNO must own or control the elements of the network infrastructure necessary to provide services to subscribers over the licensed spectrum.

A mobile network operator typically also has the necessary provisioning, billing and customer care computer systems and the marketing, customer care and engineering organizations needed to sell, deliver and bill for services, however, an MNO can outsource any of these systems or functions and still be considered a mobile network operator.